Ocular hemodynamic alterations in patients of Type 2 diabetes mellitus

Purpose: To study ocular blood flow velocity in the ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary artery in patients with Type 2 diabetes. Materials and Methods: The retrobulbar circulation in 46 eyes of Type 2 diabetic patients was compared with age-matched 21 nondiabetic eyes. The diabetic subjects were further divided into diabetics with no-clinical retinopathy (n = 24) and with either preproliferative or proliferative retinopathy (n = 22). Philips HD11XE machine was used for performing Color Doppler imaging. Results: The end-diastolic velocity (EDV) in OA was 3.21 cm/s in the preproliferative/proliferative group as compared to 6.0 and 8.5 cm/s in no-retinopathy and control group, respectively. The peak systemic velocities and EDVs of CRA in the diabetic group were significantly lower than those of normal subjects regardless of the retinopathy. The resistivity index (RI) of CRA was 0.81 in diabetic group and 0.70 in control group, which was statistically significant. Conclusion: The study showed reduced blood flow velocity and increased RI in Type 2 diabetic patients as compared to normal healthy individuals. There are significant changes noted in retrobulbar flow in patients with diabetic retinopathy as compared to patients without retinopathy.